Inflatable structures, such as boats and rafts having one or more buoyancy chambers, are normally inflated through a valve or valves through which air or gas from a pump or compressor can be directed for filling the chambers. Alternatively, compressed gas cylinders or cartridges can be utilized to quickly inflate the chambers, such as in life rafts.
Once filled, the pressure in the buoyancy chamber can vary as the gas or air expands and contracts in response to temperature fluctuations. A topping valve is often mounted on the structure for providing the final top fill of gas such that the structure can be inflated to the desired pressure. Conventional topping valves include a first body member mounted in the inflatable structure. The body includes inflation ports and a passageway adapted to receive a nozzle or the like from a hand pump so that air can be directed through the passageway and the inflation ports and into the buoyancy chamber of the inflatable structure. A flexible seal member is normally biased into sealing engagement with the inflation ports so as to prevent air from escaping rearwardly through the ports. A cap is threadably received within the passageway of the body so as to prevent collection of dirt, sand and other foreign matter within the passageway.
In white water rafting excursions, the boat or raft is inflated, sent down the river, then deflated and transported back to the starting point for another trip down the river. After deflation, the cap is screwed in to the body to keep the passageway clean during transportation so that the raft can again be easily inflated. Similarly, in military use, inflatable assault boats and rafts are often used to carry troops to the beach, then deflated and buried in the sand while the troops move inland. The cap keeps the body passageway free from sand so that the boat can be easily inflated after it is unburied.
Some topping valves have no ability to allow deflation through the valve. Other topping valves have a spring loaded poppet which must be manually held down to deform a seal so as to allow deflation through the valve. Other topping valves allow deflation by unscrewing a valve component, but require that same component to be screwed open and then shut while the air line or hose is in position during inflation. Thus, all of these prior art topping valves have deficiencies in the inflation and/or deflation mechanism.
Accordingly, a primary objective of the present invention is the provision of an improved topping and dumping valve for inflatable structures.
Another objective of the present invention is the provision of a valve which allows for quick and easy inflation and deflation of inflatable structures. Another objective is the provision of a valve which allows a structure to be inflated without unscrewing the valve components.
Another objective is the provision of a topping and dumping valve which is moved to a first position for inflation and a second position for deflation.
A further objective of the present invention is the provision of a topping and dumping valve which is economical to manufacture and durable and safe in use.
These and other objectives will become apparent from the following description of the invention.